Observation of a DC voltage induced by a steady magnetic field: A possible electromagnetic breakdown of Lorentz invariance?

A recently proposed electromagnetic test of the breakdown of local Lorentz invariance, based on the detection of a nonzero force between a circular stationary current and a charge (both at rest in the Earth frame), has provided positive evidence for such an effect. We analyze in detail the experimental results obtained, together with their implications. Possible theoretical interpretations are briefly discussed. It is shown that the corresponding values found for the parameters of Lorentz invariance violation are consistent with the existing upper limits.